1. Field of the Invention
The present invention relates to a pointing device, and more particularly, to a pointing device with multiple view angles.
2. Description of the Prior Art
An interactive multimedia system generally comprises a monitor, an interactive module, and a pointing device. Take a video game console, Wii, for example. The Wii console is the interactive module, and the Wii remote is the pointing device. The interactive module controls contents displayed on the monitor according to positional information provided by the pointing device. The pointing device senses a reference point to obtain the positional information, and provides the information to the interactive module. More specifically, the reference point is a light source near by the monitor, and the pointing device comprises a lens, an image sensing device, and a processor. The light source is sensed by the image sensing device through the lens for generating an image. The processor then obtains the positional information according to a position of the reference point in the image.
A sensing range of the pointing device is determined by selection of lenses. For example, when utilizing a lens with wide view angle, the pointing device has a wider sensing range, and the reference point has less possibility to be out of the sensing range. However, an image of the reference point formed in the pointing device is smaller, such that the pointing device can not be placed far away from the reference point. On the contrary, the pointing device utilizing a lens with narrow view angle can be placed at a longer distance from the reference point. However, the reference point has higher possibility to be out of the sensing range. Therefore, in the prior art, manufacturers of the pointing devices are not able to give consideration to both the sensing distance and the view angle of the pointing device.